Duplex-immunoassay of ovarian cancer biomarker CA125 and HE4 based carbon dot decorated dendritic mesoporous silica nanoparticles

Icariside II induces ferroptosis through the down-regulation of SLC7A11 in ovarian cancer

BACKGROUND

Ovarian cancer (OV) is the leading cause of death among gynecological malignancies. This study aimed to investigate the influence of Icariside II on OV in vitro and in vivo and to elucidate whether Icariside II induces ferroptosis in OV cells by regulating SLC7A11 expression.

METHODS

SKOV3 cells and OV nude mice were treated with Icariside II, a control-plasmid or an SLC7A11-plasmid. EdU assay, flow cytometry, wound-healing assay, and Transwell assays were used to assess cell proliferation, apoptosis, migration, and invasion respectively. Total iron, Fe2+ levels, and intracellular lipid reactive oxygen species (ROS) stimulation were evaluated in both cells and tissues. Levels of cysteine (Cys), glutathione (GSH), and glutathione peroxidase 4 (GPX4) were also analyzed. Ferroptosis markers, including Ptgs2, Chac1, SLC7A11, and apoptosis-associated genes (Bax and Bcl-2), were detected using qRT-PCR, western blotting, and immunohistochemistry (IHC). SLC7A11 expression in OV was explored using data from The Cancer Genome Atlas (TCGA), and validated with IHC staining.

RESULTS

Icariside II-induced ferroptosis in OV cells was confirmed by elevated Fe2+ and total iron levels, enhanced lipid ROS levels, higher Ptgs2 and Chac1 mRNA levels, and reduced levels of SLC7A11, Cys, GSH, and GPX4 in both in vitro and in vivo models. These effects were partially reversed by the SLC7A11-plasmid. Moreover, Icariside II suppressed SKOV3 cell proliferation, inhibited cells migration and invasion, and promoted apoptosis by downregulating SLC7A11 expression. Furthermore, we found that SLC7A11 expression was upregulated in OV tissues compared to adjacent non-tumor tissues.

CONCLUSION

Icariside II induces ferroptosis in OV by downregulating SLC7A11 expression in vitro and in vivo. Our study identified Icariside II as a promising therapeutic agent for the treatment of OV.

Current development of theragnostic nanoparticles for women's cancer treatment

In the biomedical industry, nanoparticles (NPs-exclusively small particles with size ranging from 1-100 nanometres) are recently employed as powerful tools due to their huge potential in sophisticated and enhanced cancer theragnostic (i.e. therapeutics and diagnostics). Cancer is a life-threatening disease caused by carcinogenic agents and mutation in cells, leading to uncontrolled cell growth and harming the body's normal functioning while affecting several factors like low levels of reactive oxygen species, hyperactive antiapoptotic mRNA expression, reduced proapoptotic mRNA expression, damaged DNA repair, and so on. NPs are extensively used in early cancer diagnosis and are functionalized to target receptors overexpressing cancer cells for effective cancer treatment. This review focuses explicitly on how NPs alone and combined with imaging techniques and advanced treatment techniques have been researched against 'women's cancer' such as breast, ovarian, and cervical cancer which are substantially occurring in women. NPs, in combination with numerous imaging techniques (like PET, SPECT, MRI, etc) have been widely explored for cancer imaging and understanding tumor characteristics. Moreover, NPs in combination with various advanced cancer therapeutics (like magnetic hyperthermia, pH responsiveness, photothermal therapy, etc), have been stated to be more targeted and effective therapeutic strategies with negligible side effects. Furthermore, this review will further help to improve treatment outcomes and patient quality of life based on the theragnostic application-based studies of NPs in women's cancer treatment.

In Situ Synthesis of Highly Fluorescent, Phosphorus-Doping Carbon-Dot-Functionalized, Dendritic Silica Nanoparticles Applied for Multi-Component Lateral Flow Immunoassay

The sensitivity of fluorescent lateral flow immunoassay (LFIA) test strips is compromised by the low fluorescence intensity of the signaling molecules. In this study, we synthesized novel phosphorus-doped carbon-dot-based dendritic mesoporous silica nanoparticles (DMSNs-BCDs) with a quantum yield as high as 93.7% to break this bottleneck. Meanwhile, the in situ growth method increased the loading capacity of carbon dots on dendritic mesoporous silica, effectively enhancing the fluorescence intensity of the composite nanospheres. Applied DMSNs-BCDs in LFIA can not only semi-quantitatively detect a single component in a short time frame (procalcitonin (PCT), within 15 min) but also detect the dual components with a low limit of detection (LOD) (carbohydrate antigen 199 (CA199) LOD: 1 U/mL; alpha-fetoprotein (AFP) LOD: 0.01 ng/mL). And the LOD of PCT detection (0.01 ng/mL) is lower by 1.7 orders of magnitude compared to conventional colloidal gold strips. For CA199, the LOD is reduced by a factor of four compared to LFIA using gold nanoparticles as substrates, and for AFP, the LOD is lowered by two orders of magnitude compared to colloidal gold LFIA. Furthermore, the coefficients of variation (CV) for intra-assay and inter-assay measurements are both less than 11%.

Cancer Marker Immunosensing through Surface-Enhanced Photoluminescence on Nanostructured Silver Substrates

Nanostructured noble metal surfaces enhance the photoluminescence emitted by fluorescent molecules, permitting the development of highly sensitive fluorescence immunoassays. To this end, surfaces with silicon nanowires decorated with silver nanoparticles in the form of dendrites or aggregates were evaluated as substrates for the immunochemical detection of two ovarian cancer indicators, carbohydrate antigen 125 (CA125) and human epididymis protein 4 (HE4). The substrates were prepared by metal-enhanced chemical etching of silicon wafers to create, in one step, silicon nanowires and silver nanoparticles on top of them. For both analytes, non-competitive immunoassays were developed using pairs of highly specific monoclonal antibodies, one for analyte capture on the substrate and the other for detection. In order to facilitate the identification of the immunocomplexes through a reaction with streptavidin labeled with Rhodamine Red-X, the detection antibodies were biotinylated. An in-house-developed optical set-up was used for photoluminescence signal measurements after assay completion. The detection limits achieved were 2.5 U/mL and 3.12 pM for CA125 and HE4, respectively, with linear dynamic ranges extending up to 500 U/mL for CA125 and up to 500 pM for HE4, covering the concentration ranges of both healthy and ovarian cancer patients. Thus, the proposed method could be implemented for the early diagnosis and/or prognosis and monitoring of ovarian cancer.